Smily.
Any battery charger will look at the batteries "weakest" cell and charge accordingly.
With a Univolt, if there is more than 25 points difference between the weakest and best cell, the charger will overcharge. It's not the chargers fault, it's the condition of the battery.
A charging sysytem in a car is OK for up to 50 points difference in specific gravity. Not so with Univolts or Intelli-chargers. 25 points is the maximum.
Therefore a good Univolt will not overcharge a good battery, but will overcharge a weak celled battery.
So what would be the opinions on leaving the AS connected to shore power while being stored (short term) I have been keeping mine " on charge" while parked in the driveway since I noticed my batteries starting to fade last winter. So farthey have held a charge well, but are sealed so I can't check fluid levels.
I am having the same problem with brand new batteries.
I have replaced them twice inside of 5 months. ( fortunately Wal mart will exchange with little question). I now turn my Univolt on only when my batteries are weak and I let it run for about eight hours and turn it back off.
Anyway, The "points" that you refer to, are they controlled by the owner and are they supposed to be optimal at time of purchase?
Can you please give me a short pointer on "points"?
thanks for your attention to this matter
Smily
__________________ Ken Smillie
My 1994 36' Classic MH is for sale See it in the classifieds
The question becomes "when will a battery cell become weak."
It can usually be predicted by how old the batteries are compared to the quality of the batteries expected life.
A 12 month battery will last, on an average of 12 months. Again, that's an average.
If it was my trailer, and the batteries are near their expected life, I would watch the charging system, so that overcharging might be kept to a minimum. However, if the battery has weakened, which will tell the charging to "keep on going," then I would disconnect the batteries or replace them.
Unfortunately, sealed batteries cannot be checked for water level. The older battery water consumption was a great indicator of it's condition, namely if you started to use an appreciable amount of water in a short period of time, the batteries were done.
If I had a doubt, I would not plug the trailer into city power, until I knew the exact condition of the batteries.
The condition of the battery is determined by the specific gravity of the water. A very weak battery will read perhaps 1100, a fair battery condition will read between 1200 and 1250, and a fully charged battery will read between 1275 to 1300.
Points is the difference in specific gravity readings from one cell to the other. 25 points maximum is between the best and worst cell. The best time to measure the specific gravity with a hydrometer, is when the battery is reasonably well charged.
I have worked at Point Loma in SD many time and I noticed that the weather man always mentioned rain in his forcast. After many trips I concluded that the only reason that they mention rain is so people will not forget what it is. LoL.
Ironically, I took my wife to SD for our honeymoon. I told her we were going there because the weather is always perfect.
Wouldnt you know it, It was raining when the plane landed and it rained until we took off to Las vegas three days later. We had to go to the mall and buy jackets because it was cold.
Anyway, whoever said it never rains in southern california?
Smily
__________________ Ken Smillie
My 1994 36' Classic MH is for sale See it in the classifieds
Gordon, you may have an ideal system that works perfectly, but others do not. Iv'e never had a fully charged battery that worked the way you describe. Do you have a battery monitor to keep the battery charged when not in use??Just took my deep cell marine battery out and recharged it. It's been in the trailer on the Univolt , intermittingly for about 5 months. I'm only getting about 12.35 reading from the voltmeter.
Smily, one suggestion: Flip the breaker on the Univolt to cut out the power to it, you'll still have AC power elseware. Use a good charger to keep the batteries charged for 12v power and recharge over night! Use the battery during the day for 12v power. This may not work so well if you need heat all day & night.
Tom
__________________
There is Something Worse than Dying--- That is NOT LIVING !!!
PERFECT Trailer- Dog loves it- Wife hates it!!! You're not camping until you're miserable!
My 1976 Argosy Motorhome unit acts as though the coach battery is not connected to the system. I can get all 12 Volt accesorries to run off of the engine battery by turning the ignition key to the accessory position, and all 110 volt outlets work when plugged into a 110 volt outlet. The Univolt is putting out sufficient 12 volt power (13.5 to 16 Volts), but the 12 volt stuff would not work off of the Univolt, or without turning the ignition key to the accessory position.
Then I ran another ground wire from the negative coach battery to the chassis ground, and now all 12 volt stuff will work off of the Univolt, but still no 12 volt stuff when Univolt is unplugged, and ignition key is off.
I suspect that the positive terminal to the coach battery, or the positive side of the coach load, is not properly connected. Is there a battery cutoff switch hidden somewhere that I am not finding, or can I just run another test lead from the poitive terminal to the positive side of the univolt, and should it be fused. Finally, I suspect maybe a bad ammeter, or loose wire in the control panel may be the culprit.
Any suggestions?
Chas
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Thank you
There was no factory installed cut off switch. A PO may have added one. The wire from the battery box runs from the battery to the fuse panel, thats it. I would check the routing of this wire to see. You could also have some sort of relay that was installed by a PO that acts as a disconnect and it has failed. Continuous duty relays are not cheap, so many folks by the inexpensive ones and they then fail in short order.
Happy tracing!
__________________
Brett G
WBCCI #5501 AIR # 49
"Stop worrying about the potholes in the road and celebrate the journey." -- Fitzhugh Mullan
Wise men talk because they have someting to say; fools, because they have to say something. -- Plato
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I am studying the UNIVOLT and I see many opinions on the Function of the Univolt.
Does the Tow vehicle provide 12 volts to the trailer or the trailer battery via the Univolt?
Looking for the facts only,
Smily
The tow vehicle does not provide DC voltage to the battery through the Univolt, It is provided through a separate feed wire to the battery.
Terry
I am having a problem with my 12v system on my 73 Sovereign. I do not believe there are any shorts or draws although it is possible. The problem seems to be occassional. At times 12v power is very weak or dead, even when I have had the coach plugged in to shore current for a while. On occassion I have unplugged shore current and reconnected to shore current and voila the 12v system is working again. Also, I don't know if this has anything to do with the problem or just old control panel guages but my ammeter does not work at all and my battery level never reads above fair even with a new, charged battery.